[PATCH] fbdev: statically link the framebuffer notification functions

The backlight and lcd subsystems can be notified by the framebuffer layer
of blanking events.  However, these subsystems, as a whole, can function
independently from the framebuffer layer.  But in order to enable to the
lcd and backlight subsystems, the framebuffer has to be compiled also,
effectively sucking in a huge amount of unneeded code.

To prevent dependency problems, separate out the framebuffer notification
mechanism from the framebuffer layer and permanently link it to the kernel.

Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 46 insertions, 0 deletions

diff --git a/drivers/video/fb_notify.c b/drivers/video/fb_notify.c
new file mode 100644
index 000000000000..8c020389e4fa
--- /dev/null
+++ b/drivers/video/fb_notify.c
@@ -0,0 +1,46 @@
+/*
+ *  linux/drivers/video/fb_notify.c
+ *
+ *  Copyright (C) 2006 Antonino Daplas <adaplas@pol.net>
+ *
+ *      2001 - Documented with DocBook
+ *      - Brad Douglas <brad@neruo.com>
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file COPYING in the main directory of this archive
+ * for more details.
+ */
+#include <linux/fb.h>
+#include <linux/notifier.h>
+
+static BLOCKING_NOTIFIER_HEAD(fb_notifier_list);
+
+/**
+ *      fb_register_client - register a client notifier
+ *      @nb: notifier block to callback on events
+ */
+int fb_register_client(struct notifier_block *nb)
+{
+        return blocking_notifier_chain_register(&fb_notifier_list, nb);
+}
+EXPORT_SYMBOL(fb_register_client);
+
+/**
+ *      fb_unregister_client - unregister a client notifier
+ *      @nb: notifier block to callback on events
+ */
+int fb_unregister_client(struct notifier_block *nb)
+{
+        return blocking_notifier_chain_unregister(&fb_notifier_list, nb);
+}
+EXPORT_SYMBOL(fb_unregister_client);
+
+/**
+ * fb_notifier_call_chain - notify clients of fb_events
+ *
+ */
+int fb_notifier_call_chain(unsigned long val, void *v)
+{
+        return blocking_notifier_call_chain(&fb_notifier_list, val, v);
+}
+EXPORT_SYMBOL_GPL(fb_notifier_call_chain);